/Engine/Plugins/Enterprise/DatasmithImporter/Source/DatasmithImporter/Public/ObjectElements/DatasmithUObjectElements.h
Get the material name in the material slot SlotId
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Category="Datasmith | Element") [FString](API\Runtime\Core\Containers\FString) GetMaterial ( int32 SlotId )